1. Field of the Invention
The present invention relates to improvements in or relating to incubators, and in particular, although not solely to a low noise incubator space multi-modal incubator for human babies which is capable of easy maintenance yet provides efficient incubation.
2. Description of the Prior Art
Modern incubators at hospitals are complex machines which are adapted to maintain the premature or sickly baby in a controlled environment. It is standard nowadays for not only the temperature to be controlled but also the humidity and oxygen content of the air which is passed through the chamber in which the baby rests.
Many conventional or existing incubators include water tanks which are used to provide humidification of the incubator atmosphere. Such water is ideally situated underneath the bed portion and air is blown as required thereover to be both heated and humidified as required. However, the big difficulty with incubators of this type is the fact that sterilization of the unit is a time consuming and often incomplete task, owing to the fact that much of the area which must be sterilized is often at a difficult place to reach, especially filling and draining devices. Another major disadvantage is the fan noise in the enclosed environment which can damage a baby's hearing permanently.
U.S. Pat. No. 3,076,451 dated Feb. 5, 1963 of George H. Stoner Assignor to Air Shields Inc. discloses an infant incubator of an air circulatory type which has a fan located below the bedding surface so as to force air to pass through a plurality of chambers and through a humidity control device before it passes into the occupant space. Primarily the invention of that patent was the arrangement of a cooling chamber and a humidifying chamber in parallel on the air flow circuit so as to maximise the humidification effect owing to the fact that a proportion of the air flow which is not cooled undertakes the actual entrainment of moisture step. Such an incubator however was designed without the question of noise levels in mind and no disclosure is made or even contemplated which would result in the effect of the fan noise being isolated from an occupant of the incubator space. In fact, with the fan positioned in a plenum chamber as would appear to be the case the noise would tend to be excessive and and hence the incubator of U.S. Pat. No. 3,076,451 would be both both noisy and impossible to clean while the space is being occupied.
U.S. Pat. No. 3,464,388 dated Sept. 2, 1969 in the name of R. W. Stout discloses a Gnotobiotic System which includes a controlling unit which monitors the environment of a plurality of slave environments. While one of the units of the overall system shows the use of a blower or fan which is detachable and which is mounted externally of the means defining the incubator space such a system was devised without noise levels in mind and in this regard no consideration has clearly been given to the question of isolating the effect of any fan noise from the environment. While such a blower as is used in the system includes an intake filer there is clearly no disclosure of a humidifier being interposed between the blower together with a bacterial filter in order to minimise noise.
U.S. Pat. No. 3,335,713 dated Aug. 15, 1969 to J. R. Grosholz et al assignors to Air Shields Inc. discloses a circulation system of or for an incubator which can be oxygen enriched and which ensures the oxygen when used is subject to a filtering action. The filter utilized not only filters the make-up air but also filters any oxygen that may be used. The make-up air is introduced into the system through the filter and from thence by pipe lines through a blower into the incubator space itself. Again no question of sound isolation is apparent. Persons skilled in the art when viewing for example, FIG. 3 of U.S. Pat. No. 3,335,713 will envisage the possible harmful sound levels that would be generated thereby.
There is therefore some desire to provide a low sound level incubator which preferably also has additional efficiencies built thereinto to ensure that the incubator can be used to its best advantage.
It is therefore an object of the present invention to provide a method and/or means which will go at least some way to meet some of the abovementioned desiderata or which will at least provide the public with a useful choice.